Author Topic: Discovery STS-41 – Tales of Brave Ulysses  (Read 10118 times)

Offline Ares67

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #40 on: 10/01/2016 07:20 PM »
DIRECT INSERTION

Discovery, making her 11th flight, will be launched at a 28.5-degree inclination into a 160-nautical mile orbit, later to be changed into 177 by 160 miles, 160 by 156 and finally 157 by 156 nautical miles. Total weight at lift-off is approximately 4,523,894 pound, whereby Discovery, including her 48,812 pound payload, weighs 293,019 pounds. For an October 5 launch, the window opens at 7:35 a.m. EDT and extends for two hours and 22 minutes. By October 8, the window, shifting about a minute a day, opens at 7:38 a.m. and lasts for two hours five minutes.

The ascent profile for this mission is a direct insertion. Only one Orbital Maneuvering System thrusting maneuver, referred to as OMS-2, is used to achieve insertion into orbit. This direct-insertion profile lofts the trajectory to provide the earliest opportunity for orbit in the event of a problem with a Space Shuttle Main Engine. The OMS-1 thrusting maneuver after MECO plus approximately two minutes is eliminated in this direct-insertion ascent profile; it is replaced by a five-foot-per-second RCS maneuver to facilitate the Main Propulsion System propellant dump.

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #41 on: 10/01/2016 07:21 PM »
DOGGONE TOUGH

The solar cells typically used on near-Earth spacecraft cannot provide enough power for Ulysses when it is out near Jupiter, where sunlight is only four percent as strong as it is on Earth. Thus, the spacecraft derives its power from a Radioisotope Thermoelectric Generator. It is not a nuclear reactor, but simply a quantity of safely encapsulated plutonium dioxide that decays over a period of time. This decay releases heat, which is converted into electricity by thermocouples. The generator delivers about 290 watts of power in this manner. Similar power supplies have been used successfully on two Pioneer deep space probes, both Voyager spacecraft and the Galileo mission to Jupiter.

It’s the second time an RTG will be launched aboard the shuttle. Galileo, which uses two RTGs, was subject to various protests by environmental groups during its 1989 launch. The groups feared an accident could have released plutonium. Milt Heflin, who is lead flight director for STS-41, was flight director for Galileo’s deployment. “I characterized the RTGs then as doggone tough, and I haven’t changed my mind,” he says.

“I don’t have any worries about the RTG. I never have had any worries about the RTGs,” he says. Every member of the flight crew has also expressed confidence saying that they will have their families on hand for Discovery’s launch. “Quite frankly, I haven’t spent too much time worrying about the RTG situation,” says Dick Richards. “My family is going to be down there in Florida, standing underneath Discovery, waving goodbye as we go off the launch pad. So, I don’t have any problems with the RTG and am confident that the system doesn’t provide any hazard to anyone on the ground.”

This is echoed by Mission Specialist Tom Akers, who says that the Ulysses RTG would survive a Challenger-like accident. “We have looked at the statistics and the studies and our conclusion is that it’s definitely as safe as it can be and we’re not worried about it. The three people I think the most of – my wife and two kids – are going to be as close as anybody to the shuttle” when it’s launched, Akers says.

Any discussion involving nuclear issues tends to be obfuscated by emotions and exaggeration, and Ulysses is no exception. One NASA scientist, when pressed, declared, “I can understand the protestors’ concern. Our government hasn’t exactly made a name for itself on the nuclear issue.”

But in fact, the space agency has extensively tested the protective casings for RTGs, assessing their integrity in all kinds of accident scenarios. NASA studies state the chance of a plutonium release during launch is one in six million and one in 4,200 during deployment. NASA Ulysses Manager Willis Meeks says that the worst case scenario is that an accident might cause about 300 to 400 additional cancer deaths in the world population of four billion people in the next 50 years. The consensus among most informed reviewers is that the threat from the RTGs is negligibly small. And, grumbles an impatient ESA project manager Derek Eaton, “The analyses have cost as much as the spacecraft.”

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #42 on: 10/01/2016 07:27 PM »
A 360-MILE HOLE IN ONE

“Every one of us has a job to do to get Ulysses deployed successfully.”

- Thomas Akers, Mission Specialist STS-41


Two hours into the mission, the crew will begin checkout of Ulysses and the upper stages. Three centers are involved with the checks. In addition to Houston, the Ulysses Payload Operations Control Center (UPOCC, pronounced “U-pock”) at the Jet Propulsion Laboratory in Pasadena, California, oversees the spacecraft. The Consolidated Space Test Center (CSTC, pronounced “C-stick”) at the Onizuka Air Force Station in Sunnyvale, California, handles checkout for the IUS.

Standard IUS/spacecraft checks, as performed on past missions, will last about four hours. “The four-hour period is very busy, and we have a lot of work to do,” Heflin says. “We also have some fall backs in case we get into any problems.”

For example, normal commands to the IUS are sent from CSTC through the orbiter, and this link will be tested. I addition, a “direct check” will be made where the Sunnyvale center sends a command directly to the IUS from a ground station. Direct commanding will be used as a backup in case the orbiter link to the IUS fails.

A crucial set of navigation alignments will be made just prior to deployment of Ulysses. The spacecraft attempts to reach a 100-mile-wide window that is 500 million miles away. “As an analogy, since I play golf, if you equate that 100-mile window to a 4.5-inch golf course hole, we’re trying to make a 360-mile hole in one,” Mission Commander Dick Richards says.

“We are planning a series of maneuvers that Bob will be doing prior to deployment where we wil actually maneuver to different attitudes. Those attitudes will be measured by the ground and then compared with the attitude Ulysses’ Inertial Upper Stage shows to make its attitude reading matches the actual attitude of the orbiter,” he says. “It will probably be one of the more critical points of the deployment.”

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #43 on: 10/01/2016 07:30 PM »
PRETTY SPORTY

Mission Specialist Tom Akers will perform the deploy duty, assisted by Bruce Melnick. To allow direct communication with Earth during systems checkout, they will tilt the IUS/Ulysses to 29 degrees. The crew will receive a go for deploy at five hours 41 minutes into the flight. They will raise the doughnut-shaped tilt table holding the Ulysses stack to 58 degrees above the level of the payload bay a couple of minutes later.

The orbiter’s RCS thrusters are inhibited, and the Super Zip ordnance separation device physically separates the IUS and spacecraft combination from the tilt table. Compressed springs provide the force to jettison the stack from the orbiter payload bay. The Ulysses stack will shove off from the cradle six hours two minutes into the flight while the orbiter is over the Pacific approaching the west coast of the U.S. The tilt table is lowered to minus six degrees after deployment. Approximately fifteen minutes after the stack has been released, Discovery’s OMS engines are ignited to separate her from the IUS/Ulysses combination.



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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #44 on: 10/01/2016 07:31 PM »

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #45 on: 10/01/2016 07:32 PM »
“We will throw the switches that deploy the satellite, and it will be pushed out of the payload bay on springs at about five to six inches per second,” Akers says. “At that point, Shep has already set up all the cameras that are going to take the pictures of the deploy.”

“That’s a very standard deploy for us with IUS flights,” Heflin says. “It is no different than what we did for Magellan and Galileo.” The difference surfaces when the Ulysses stack begins the first of three solid rocket burns 65 minutes after deployment. “From the time that the first stage ignites until the last burn is a very short amount of time,” Heflin says.

The first IUS stage will fire for two minutes 30 seconds as the spacecraft passes over the Indian Ocean. Less than two minutes later, the second stage of the IUS will fire for one minute 47 seconds. Less than two minutes exist between the end of the second IUS burn and the PAM ignition. During that time, the PAM, which achieves stabilization revolving like a phonograph record, has to be spun up to 70 rpm.

“The PAM is spun up much like we used to do when we were deploying satellites from the orbiter,” Heflin says. The third engine will fire for one minute 30 seconds. Less than ten minutes later, the spacecraft will be “despun” to about seven rpm and the PAM detached – Time: Seven hours 24 minutes into the flight.

“II would characterize it as a pretty sporty way of getting Ulysses on its way,” Heflin says. “It will become the fastest spacecraft to date. It travels at a speed that would take it something less than 45 minutes to circle the Earth if it were still in orbit.”

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #46 on: 10/01/2016 07:33 PM »
MUCH MORE FUN UNDER THE SUN

Having completed the Ulysses deployment, the crew will then settle into the routine of operating their nine secondary payloads as well as performing medical checks and taking Earth photographs. Two of the secondaries are located in the cargo bay:

The Shuttle Solar Backscatter Ultraviolet (SSBUV) experiment will make the second of its yearly flights, having first flown on STS-34 in October 1989. The system, contained in two garbage-can-size canisters mounted on the sidewall of the payload bay, measures the ozone in the upper atmosphere. The readings will be taken at the same time and location as readings by similar sensors aboard the NOAA-9 and Nimbus 7 weather satellites.

“With those calibrations, we’ll be able to get a better feel for how the ozone layer is deteriorating around the Earth,” says Melnick, who, assisted by Akers, will be responsible for operation of the experiment.

The long-flying sensors aboard the weather satellites can degrade over time. The finely-tuned shuttle sensor will be compared against them to calibrate the on-going satellite readings. Such calibrations using the shuttle will be made each year.

Intelsat Solar Array Coupon (ISAC) is a recently added experiment which could yield valuable information for the planned rescue mission of a stranded Intelsat VI satellite. The Intelsat was not designed for low Earth orbit, where atomic oxygen in the upper traces of the atmosphere can erode materials. Samples of material like that on the satellite solar arrays have been attached to “witness plate” on the orbiter’s Remote Manipulator System robot arm.

“We’re going to take the arm and put it out over the side and basically put those witness plates into the wind (into the velocity vector, the direction the shuttle was travelling, so that the atomic oxygen would strike them),” says Heflin. The arm will be positioned over the orbiter’s side for just over 24 hours beginning on Flight Day 2 at about one day, four hours into the mission.

Just a day “in the wind,” although no real wind exists, is expected to be enough to yield data on how well Intelsat materials hold up to erosion from atomic oxygen. “It was never really designed to be living where it’s at right now. The question is how long can it stay there and then be reboosted to a useful life,” says Shepherd, who will operate the RMS along with Akers.

A rescue mission to reboost the Intelsat is scheduled for the first flight of Endeavour in early 1992. “The primary purpose of this experiment is to provide confidence that the satellite will be in good shape when we go fix it,” Dick Richards says.


Six experiments are stowed in the middeck:

- One experiment continues plant growth studies begun on previous shuttle flights. The Chromosome and Plant Cell Division Experiment (CHROMEX-2) studies plant root growth, root tip chromosome partitioning and root tip cell division patterns in microgravity. Shepherd, backed by Cabana, will oversee the experiment during the flight.

- Another experiment looks towards the testing equipment for the coming space station era. The Voice Command System (VCS) features a voice recognition device which allows voice control of a system. For its first trial, Shepherd and Melnick will attempt to use the system to control the shuttle’s closed circuit television system. They will select, pan, and tilt the cameras by voice.

- “An interesting experiment involves creating a controlled fire onboard,” says Richards. The Solid Surface Combustion Experiment (SSCE) utilizes a combustion chamber to collect data on the spread of fire over the surfaces of fuels – small filaments of paper – in microgravity, with the aim of improving spacecraft fire safety. The fires will only last seven seconds in a sealed chamber. Photographs will record the spread of the flames and the heating patterns. Melnick, assisted by Akers, will run the tests.

- Another experiment also continues research begun on previous shuttle missions. Investigation into Polymer Membrane Processing (IPMP) will test ways of producing better membranes used as fine filters in medical and other commercial applications. The pores of membranes formed by a chemical process in weightlessness are expected to be more uniform than possible on Earth. A similar project, by Battelle Lab’s Advanced Materials Center, flew aboard STS-31 in April 1990.

- Another experiment actually houses the majority of the STS-41 crew (in numbers) – 16 laboratory rats sealed in a middeck locker. The Physiological Systems Experiment (PSE) will determine the effects of a “proprietary,” meaning a commercial trade secret, protein on the rats’ physiological systems in microgravity.

- As with all shuttle flights, radiation monitoring tests are continuing, although not with the “phantom head” flown on several flights. Radiation Monitoring Experiment RME-III was designed to measure gamma radiation in the shuttle’s crew module. “We’re always looking for some improved radiation monitoring equipment,” Heflin says.


As with any shuttle flight, Discovery also carries a long list of Detailed Supplementary Objectives (DSOs) and Detailed Test Objectives (DTOs). The seven medical DSOs will deal with monitoring the fluid shift that occurrs to the upper body in weightlessness, continuing the study of Space Adaptation Syndrome.

Earth observation and photography also fall under the DSO listing. “I hope we can document changes in our environment and eventually help understand how we can make Earth a safer, cleaner place for all of us to live,” Cabana says.

Most of the DTOs will deal with gathering engineering data on shuttle performance. One DTO has the crew dump propellants through the Reaction Control System jets in the shuttle’s nose as it enters the atmosphere. The fuel will be expended through opposing side jets in a test to see if the forward weight of the shuttle can be lowered, thereby helping to establish a favorable center of gravity (CG) for landing. Such a CG is presumed to be needed during emergency landings resulting from launch aborts.

“The factor here is that you want to be able to get the CG moved aft – not have a forward CG. That would make the vehicle fly better and also you don’t like to land with a lot of hypergolics (highly toxic RCS fuel) onboard from a safety standpoint,” Cabana says.

Three dumps will be made – when Discovery ias flying at Mach 12, then Mach 6, and finally Mach 4. Similar tests had been planned during Columbia’s 61-C mission in 1986, but had to be cancelled after launch when engineers discovered that the orbiter was equipped with old design jets that could have exploded under the conditions of the dump.

Discovery is equipped with different jets. “We’ve got safety built into it. We can terminate the dump at any time, and we’ll be watching our propellant as it depletes,” Cabana says.

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #47 on: 10/01/2016 07:35 PM »
SUNRISE LANDING

STS-41 is scheduled to land at Edwards Air Force Base, California. The carbon-carbon brakes, flown for the first time on Discovery during STS-31, will undergo additional testing. During STS-31, the new brakes were used on the long lakebed and were only applied at speeds under 137 miles per hour. For this flight, a normal braking profile will be used, with landing on the concrete runway and the brakes applied beginning at 160 miles per hour. These brake and landing gear modifications will eventually allow NASA to resume end-of-mission landings at Kennedy Space Center.

Landing is expected on orbit 66 after a flight of four days, two hours, seven minutes. With an October 5 launch, touchdown will occur at 6:44 a.m. PDT, at dawn over the desert.

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #48 on: 10/01/2016 07:36 PM »
SUMMARY OF MAJOR ACTIVITIES

Flight Day One

Launch and Ascent
Post-insertion checkout
Pre-deploy checkout
Ulysses/IUS deploy
CHROMEX-2
DSO/ DTO
PSE
SSBUV outgassing

Flight Day Two

Air Force Maui Optical Site (AMOS) calibration test
Ulysses/IUS backup deploy opportunity
CHROMEX-2
DSO/DTO
RMS powerup and checkout
SSBUV Earth views
VCS test #1

Flight Day Three

CHROMEX-2
DTO
SSBUV Earth views
VCS test #2

Flight Day Four

CHROMEX-2
DSO/DTO
SSBUV Earth views
VCS test #3
FCS checkout
RCS hotfire
Cabin stow

Flight Day Five

CHROMEX-2 status
DSO/DTO
PSE status
SSBUV Earth views
SSBUV deactivation
Deorbit preparation
Deorbit burn
Landing


(JSC Space News Roundup, Sep. 14, 1990; Rockwell International, STS-41 Press Information, October 1990; NASA STS-41 Press Kit, October 1990; Dixon P. Otto, Countdown, October 1990; Nicholas Booth, “Ulysses – The Long and Winding Road,” Final Frontier, Sep./Oct. 1990; Chronology of KSC and KSC related events for 1990, KHR-15, Mar. 1991 – edited)

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #49 on: 10/01/2016 07:39 PM »
Ulysses – The Road of Trials

“If any god has marked me out again
for shipwreck, my tough heart can undergo it.
What hardship have I not long since endured
at sea, in battle! Let the trial come.”


- Homer, “The Odyssey,” Book V


WHAT’S IN A NAME?

Ulysses is an international project to place a spacecraft in polar regions around the Sun. Until 1984, the Ulysses project was called the International Solar Polar Mission (ISPM). Although the name described the mission’s objectives, project officials believed it brought little romance to an undertaking they considered exciting. As a result, project officials choose a new name.

Professor Bruno Bertotti of the University of Pavia, Italy, principal investigator of the gravitational-wave experiment aboard the spacecraft, suggested “Ulysses” and cited the 26th canto of Dante’s inferno, referring not only to the adventurous trip of the mythological Greek hero after the Trojan War, but also to a most remarkable late Medieval tradition in which the spirit and the driving motives of all human explorations of unknown regions are forcefully presented.

Dante’s story says that Ulysses, after his return home to his beloved wife, Penelope, and to his kingdom in Ithaca, became bored with everyday life and the troublesome duties a s a king; with his old shipmates, he decided to start on a new journey to explore that part of the world which lay beyond the Pillars of Hercules, i.e. the Strait of Gibraltar, at that time completely unknown and unexplored.

As Dante says, there is indeed a “mondo sanza gente,” an uninhabited world beyond the Sun where there are no planets, no possibility of life, no familiar features. According to Dante, Ulysses’ crew mutinied out of fear and he exhorted them to continue “to follow after knowledge and excellence.”

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #50 on: 10/01/2016 07:42 PM »
A MATCH MADE IN HEAVEN?

The Ulysses project is a cooperative endeavor between the European Space Agency and NASA. A contractor team led by Dornier GmbH, Federal Republic of Germany, designed and built the spacecraft. Subcontractors included firms in Austria, Belgium, Denmark, France, Italy, the Netherlands, Spain, Sweden, Switzerland, the United Kingdom and the United States. The project has undergone as many twists and delays encountered by projects such as the Galileo Jupiter probe and the Hubble Space Telescope. In 1974, NASA and the European Space Research Organization (ESA’s forerunner) conducted a project definition study of an out-of-ecliptic solar probe, called International Solar Polar Mission, in which they would each develop a spacecraft – to a different design – to make simultaneous close passes over opposite poles of the Sun.

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #51 on: 10/01/2016 07:43 PM »
Development began as soon as the agreement had been signed in March 1978. According to the September 1980 Space Shuttle Flight Assignment Manifest, the NASA Solar Polar probe was scheduled to be launched on STS-35, then OV-104 Atlantis’ maiden voyage, in March 1985, followed by the ESA Solar Polar probe aboard Challenger STS-36 in April 1985. Both spacecraft were to be mounted to a three-stage planetary variant of the IUS. To achieve the desired high-inclination solar orbits, they were to make a detour via Jupiter. The two spacecraft were to fly in formation until they were through the asteroid belt, then they were to slowly diverge in order to make opposing polar passes of the giant planet so that the resulting gravitational slingshots would hurl one above, and the other below the ecliptic plane to facilitate simultaneous study of both of the Sun’s poles.

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #52 on: 10/01/2016 07:44 PM »
Delays and cost overruns with the Space Shuttle and the knife-wielding propensity of David Stockman ensured that this happy state of collaboration across the Atlantic soon was shattered. Looking back at those years ISPM seems a case history in how not to organize an international project. The fact that the solar polar mission still exists at all is a triumph in the face of adversity.

Ask Derek Eaton, the man most people cite as the mission’s motivating force, and the only one who has remained with the project since its inception. The British-born project manager for ESA has spent more than fifteen years of his career devoted to the solar probe. He bears the mien of someone who has learned the value and virtue of patience. “The main lesson I’ve learned,” he says today, “is that there’s no such thing as guarantees. Space is a risky business – you have to accept that.”

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #53 on: 10/01/2016 07:45 PM »
The cancellation of the three-stage IUS in December 1980 meant that the ISPM spacecraft would have to be reduced to fit the capabilities of the two-stage IUS, but the policy switch to the Centaur in January 1981 suddenly reversed this. The plan was to dispatch Galileo and ISPM on Centaurs, and to do this in the same 1985 window. The sting in the tail came a few months later, when Congress axed the U.S. spacecraft from NASA’s budget, causing uproar in the international space community.

The way in which NASA pulled out of the deal still rankles some European project people, who tell apocryphal versions of the story in bars or under cover of darkness. Neither ESA nor NASA officials will be drawn into the fray, but what happened was something like this: Early in 1981, the Administrator of NASA telephoned the Director General of ESA to say, in effect: The budget make-up is in, and it’s bad news, I’m afraid. We’re going to have to cancel our half of ISPM. We’re holding a press conference in an hour.”

And that was it. One NASA manager reflects: “Unilateral decisions and collaborative projects don’t really mix. We had absolutely no idea what we were letting ourselves in for.”

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #54 on: 10/01/2016 07:48 PM »
ESA decided to continue. Still miffed, European managers scored a minor victory in 1984 by unilaterally renaming the project. A number of ESA people had always hated the NASA title of “Solar Polar,” which Eaton would say is better suited to an ice cream. Professor Bertotti’s proposal of “Ulysses” seemed apt, “as the whole project had become a bit of an odyssey,” an ESA scientist says. The name was duly announced to the press in Europe before NASA could weigh in with its own candidate, and “Ulysses” it became.

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #55 on: 10/01/2016 07:51 PM »
HANDS ACROSS THE WATER

Since that nadir in the early 1980s, relations between the two agencies have improved. “We realize that the European system works differently – not better, just different,” says JPL project official Ed Massey. Derek Eaton, too, seems more tractable. “I’ve been critical of NASA in the past. But those criticisms are the sorts you’d reserve for any bureaucracy.”

Ulysses was now scheduled for a shuttle launch in May 1986. At that time, like Galileo, it would have used the hydrogen-fueled Centaur stage for the boost to Jupiter. If Challenger had not been lost, her next payload on mission 61-F would have been Ulysses. In the aftermath of the loss of Challenger, use of the Centaur was banned from the shuttle for safety reasons and the planetary probes were forced to switch to less efficient solid motor upper stages.


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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #56 on: 10/01/2016 07:57 PM »
Both Galileo and Ulysses were reassigned to June 1987, but it soon became clear that the shuttle would not return to service in time to meet that window. Furthermore, it was decided that trying to ge two shuttles off the ground in the space of a fortnight would be too heavy an operational load. NASA and ESA reached an agreement in April 1987: Galileo would take the 1989 window, and Ulysses was to follow a year later.

Derek Eaton’s single-mindedness has ensured that the spacecraft will be ready despite its many journeys through Europe, out to Cape Canaveral, back to Europe and back to the Cape again. When the spacecraft was removed from its transport/storage container in May 1989 for reintegration and recertification (the scientific experiment payload had been pulled from the spacecraft during its storage period, along with many of the subsystems), he stated, “Ulysses was in good shape when it was brought out from the container. We found it is as magnetically ‘clean’ as when we tested it in 1985.”

Ulysses is not as badly affected as Galileo by the cancellation of the Centaur and the plan to run the SSMEs at less than peak thrust. At 370 kilograms, it is 15 percent of Galileo’s mass. However, even though it has been designed for the capabilities of the planetary-IUS, it is too heavy for the two-stage variant to dispatch on the necessary high-speed trajectory to Jupiter. It is so lightweight though, that it was possible to install a 2,200-kilogram PAM-S to help accelerate the spacecraft away from the Earth, once the IUS has achieved escape velocity.

The initial plan has been for NASA’s spacecraft to carry a camera to record the solar disk and the corona, but this could not be transferred, because it would have made the remaining spacecraft too large for even the enhanced IUS, so Ulysses has no imaging capability. So, in purely PR terms, Ulysses will be hamstrung by its lack of cameras or any other imaging instruments. Anyone who’s witnessed a Voyager press conference has noted the general fidgeting and cumulative exodus of reporters during presentations on so-called “fields and particles” experiments. “Fundamental science isn’t necessarily sexy,” says David Dale, head of scientific projects at ESA. Another of the instruments developed for the NASA spacecraft was repackaged and included on the Solar Anomalous and Magnetospheric Particle Explorer (SAMPEX) satellite to be launched in 1992.

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #57 on: 10/01/2016 07:57 PM »

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #58 on: 10/01/2016 07:58 PM »

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Re: Discovery STS-41 – Tales of Brave Ulysses
« Reply #59 on: 10/01/2016 07:59 PM »

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